Interpretive Summary: Aflatoxins are toxic and cancer-inducing compounds produced by fungal molds, such as Aspergillus flavus and A. parasiticus. These compounds contaminate our food source such as corn, cotton, peanut, and tree nuts when the fungus infects crops. Gene profiling for discovery of all of the genes responsible for aflatoxin formation is absolutely necessary for the control or elimination of aflatoxin contamination in food and feed. The information obtained through genomic studies by Expressed Sequenced Tags is important to scientists and researchers for devising strategies to control aflatoxin contamination through genetic engineering of commercial crops.

Technical Abstract:
Aflatoxins are highly toxic and the most carcinogenic compounds produced by Aspergillus flavus and A. parasiticus. In an attempt to identify genes involved in aflatoxin formation, a large scale sequencing of the A. flavus Expressed Sequence Tags (EST) was carried out. The 5' ends of 26,110 cDNA clones from a normalized cDNA expression library were sequenced. After annotation, a total of 7,218 unique ESTs in A. flavus have been assembled into 3749 tentative concensus sequences and 3469 single sequences. The gene ontology (GO) terms were assigned to these ESTs. The genes that are potentially involved directly or indirectly in aflatoxin formation, such as the aflatoxin biosynthetic pathway, signal transduction, global regulation, pathogenicity of the fungus, and stress response are reported here.